Environmental lawyers say some conservative justices might want to curtail the EPA's authority to regulate power plant emissions beyond the fence line.
A new administration could renew the U.S. commitment to the Paris climate agreement, strengthen air pollution standards, and more. But that will take time.
The Trump EPA rule, replacing the Obama EPA's Clean Power Plan, combines a Clean Power Plan repeal with new, less stringent emissions reductions guidelines.
A recent study found that nearly 5 million deaths worldwide in 2017 could be attributed to stroke, heat attack, diabetes, lung cancer and chronic lung disease that resulted from air pollution.
